Built for speed, accuracy, and high-performance! The Easton Sonic 6.0 is a 6MM (.231" inside diameter) carbon shaft made using Easton's seamless Acu-Carbon process. That means 100% spine and weight consistency from shaft-to-shaft. The lighter mass weight provides a wider range of options, including lightweight high speed set-ups, or heavyweight high FOC (front of center) and high momentum arrows. 6mm H nocks installed. 6mm 18 grain ST inserts included. Compatible with standard thread broadheads and points. Sold by the 6-pack. Available in 250, 300, 340, 400, 500, and 600 spines. Please specify. Features 100% carbon fiber construction Reduced 6mm diameter 6mm H nocks installed 6mm 18 grain ST inserts included Straightness ±.003" Made in the USA Easton Sonic 6.0 Carbon Arrow Specifics Spine Point GPI Length Insert Nock 250 5/16" 9.5 32½" 6mm ST (18 grains) H 300 9/32" 8.8 32" 6mm ST (18 grains) H 340 9/32" 7.8 31½" 6mm ST (18 grains) H 400 9/32" 7.2 31" 6mm ST (18 grains) H 500 9/32" 6.7 30½" 6mm ST (18 grains) H 600 9/32" 5.8 30½" 6mm ST (18 grains) H Straightness ±.003"